Response to DC

Dear Dan,

This is a response to your comment [1] on RIF.

> This surprises me;
> 
> Table 1. Correspondence between RDF and RIF symbols.
>  RDF Symbol Example RIF Symbol Example
>  Absolute IRI <http://www.w3.org/2007/rif> Absolute IRI
> "http://www.w3.org/2007/rif"^^rif:iri
> 
>  -- http://www.w3.org/TR/2008/WD-rif-rdf-owl-20080415/
> 
> The notation <http://www.w3.org/2007/rif> in turtle, N3,
> and SPARQL is *use* of a symbol, where
> "http://www.w3.org/2007/rif"^^rif:iri is *mention*
> of a symbol.
> 
> RIF seems to be using "http://www.w3.org/2007/rif"^^rif:iri
> for use of a symbol.
> 
> Am I reading that right?

Both <http://www.w3.org/2007/rif> and "http://www.w3.org/2007/rif"^^rif:iri are ways of writing IRIs in the syntax. And, like in RDF, IRIs are uninterpreted symbols in RIF, i.e., the same IRI can be interpreted differently in different interpretations. Perhaps it is helpful at this point to clarify that rif:iri is a symbol space (i.e., a set of symbols), but not a datatype. A symbol space is like a datatype, but the value space and lexical-to-value mapping are optional (and not present in the case of rif:iri).

Finally, it has been decided that we will use <http://www.w3.org/2007/rif> as a shortcut for "http://www.w3.org/2007/rif"^^rif:iri in the syntax, and that further explanatory text will be included in the RDF and OWL compatibility document (see [2]).

does this address your concern?

Best, Jos on behalf of the RIF working group

[1] http://lists.w3.org/Archives/Public/public-rif-comments/2008May/0000.html [2] http://www.w3.org/2005/rules/wiki/SWC#Symbols_in_RIF_Versus_RDF.2FOWL_.28Informative.29

> 
> -- 
> Dan Connolly, W3C http://www.w3.org/People/Connolly/
> gpg D3C2 887B 0F92 6005 C541  0875 0F91 96DE 6E52 C29E